Improvement in mechanisms for raising and lowering propellers



Patented Aug.8,1876.

B. MITCHELL.

manners.

MECHANISM FOR RAISING AND LOWERING PROPELLERS. No. 180,778.

Jays;

WITNESSES UNITED STATES PATENT OFFICE.

BENJAMIN MITCHELL, OF HANCOCK, MARYLAND.

IMPROVEMENT IN MECHANISMS FOR RAISING AND LOWERING PROPELLERS.

Specification forming part of Letters Patent N0. 180,778, dated August8, 1876; application filed January 21, 1876.

To all whom it may concern:

Be it known that I, BENJAMIN MITCHELL, of Hancock, in the county ofWashington and State of Maryland, have invented a new and usefulImprovement in Raising and Lowering Propellers; and I do hereby declarethat the following is a full, clear, and exact description of the samereferenee being had to the accompanying drawing, forming a part of thisspecification, in which Figure 1 is a longitudinal vertical section Fig.2, a vertical cross-section.

The invention relates to means for raising and lowering the propeller ofa canal-boat, so as to adapt it to work properlyin the water whether theboat is loaded or otherwise, and so as always to preserve thepropeller-shaftin a horizontal position.

The invention consists in a propeller-shaft supported in slide-platesand raised by adjustable hangers; in an auxiliary plate at the outerbearing that moves with the bearingplate, so as always to cover the slotin the latter and prevent ingress of water; in a plate thatsimultaneously slides and revolves, to close'the slot in the fixed platein which the inner bearing moves 5 and in adapting the pinion to beoperated by the same drivewheel, in whatever position it may be placed,by means of a pinion that slides above or below the propeller-shaftpinion, according to whether the boat is empty or loaded.

A represents a canal-boat, in the stern a of which is employed a rotarypropeller, B. The latter has a bearing in the plates C C, which slidevertically, the former in the ways 0 c, and the latter on a fixed plate,D. The shaft also passes through the hangers E E, (whose shanks arethreaded,) and by means of the nuts 6 e is raised or lowered withrespect to the cross-bar E; also, through the flanged or side-groovedguide G that slides up and down on the standards H H.

In order to secure the slot an, arranged in the stern, and through whichthe propellershaft. works, from admitting waterto the boat, I make theslide-plate C with a slot, 0, and provide an auxiliary plate, K, havingthe stud it that protrudes through the slot 0.

The plates 0 K both slide in the ways a 0, the former carrying thelatter up by the stud it when the boat is loaded and the propellerraised; but when moving down to accommodate the propeller to an unloadedboat the plate C is arrested by the stud as soon as the plate K hasreached the bottom of ways and the top of slot bears upon the stud.

The bearing-plate C is provided with a pinion, I, and merely separatedtherefrom by a neck, which slides in the slot 61 of plate D. The latterhas a fixed rack, J, in which meshes the pinion I, so that the plate Cmay turn as well as slide, thus always covering the slot at andpreventing the ingress of water therethrough.

In order to drive the shaft conveniently at difl'erent elevations I usethe pinion L that moves with it and the pinion M on a slideshaft, N.

When the propeller is elevated to actuate a loaded boat, the pinion M isslided under the pinion L, so as to connect it with the drivingspur-wheel O, and when it is desired to drive an empty boat the pinion Mis placed in position over the pinion L, connecting in the same manneras before with the spurwheel. Again, by sliding back the pinion M out ofthe way, the pinion L may be brought itself into connection with thespur-wheel, so as to drive the propeller-shaft.

In this Way the propeller is very quickly thrown into position forperforming its duty with equal efliciency, no matter whether the boat isempty or loaded, and this may be done very conveniently with few handsand without much expenditure of manual labor.

Having thus described my invention, what I claim as new is- 1. Thecombination, with propeller-shaft, of plates C C, hangers E E, and guideC, arranged as and for the purpose described.

2. The auxiliary plate K, having stud 7c, in combination with a slottedslide-plate, C c, as and for the purpose set forth.

3. The slide-plate C, provided with pinion I, combined with the slottedfixed plate D d, having the rigidly-attached rack J, as and for thepurpose specified.

4. The combination, with drive-wheel O, and vertically-adjustablepropeller-shaft, having pinion L, of the slide-shaft N, having pinion M,as and for the purpose described.

BENJAMIN MITCHELL. Witnesses:

T. E. RENEHART, W. D. MITCHELL.

